you are incorrect about James Remar playing 2 characters in Django unchained. The first actor is James Russo and the other character towards the end is actually James Remar
more than half of these are not even newsworthy. They are characters that appear in alternate realities or dream sequences where the intention is that have some sort of connection to another character and only makes sense to be played by the same actor.
Love the movie, and happy I learn some more interesting facts about it
I guess it's just a good actor play :)